We assumed that the sea organism in the Jeju Island might have stronger tolerance against ultraviolet ray than other regions, so we divided and cultured Jeju Island marine algae such as Gelidium amansii ,. and then we researched the protection and therapeutic effect of apoptosis from the extracted materials, and also analyzed the anti-oxidant activity of Gelidium amansii. Gelidium amansii in Jeju Island had 0% in MTT assay, so they had no skin cell protection effect. And In the anti-oxidant activity test for Gelidium amansii , it had no inhibition value, which means that it doesn't have any anti-oxidant effect.